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Percy Spencer, Microwave Inventor
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Percy Spencer poses with his pipe

Percy Spencer

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Drawing of a candy bar melting in a shirt pocket
Drawing of a candy bar melting in a shirt pocket

Microwave Inventor

In 1945 engineer Percy Spencer was researching radar at the Raytheon company. He stopped for a minute in front of a magnetron, an electronic vacuum tube that generates high-frequency radio waves. Suddenly feeling a strange sensation, he noticed that the chocolate bar in his pocket was melting.

Intrigued, Spencer placed popcorn kernels near the magnetron; soon popcorn was popping out over the lab floor. Spencer then put a raw egg in a pot in front of the magnetron. The exploding egg splattered a nearby coworker, confirming that microwaves could cook food quickly and unconventionally.

Spencer and other Raytheon company engineers went on to develop the first microwave oven.

Next: What Were the First Microwave Ovens Like? ›

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